Function emit_hl_marshal_result 

pub fn emit_hl_marshal_result(
    s: &mut State<'_, '_>,
    id: Ident,
    rt: &Result<'_>,
) -> TokenStream

Emit code to marshal the result of a function with result type rt from a Rust value named by id. The resultant token stream will be an expression that which typechecks as Vec<u8>.

Precondition: the result type must only be a named result if there are no names in it (a unit type)